talekutil usage instructions default trustdomainindex, name, and address when outputting sharable replica.pub.json files

[mixmasala]

the usage intstructions in cli/talekutil/README.md show using talekutil --trustdomain to output json for each replica that is later aggregated into a client configuration.

However, talekutil sets the --index, --address, and --name flags from the default values, which loses the parsed values from the configuration.

The remedy is to not parse these flags when --infile is specified, or to amend these instructions to specify these flags.